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Brian Hoff

Publications and source records attributed to Brian Hoff.

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Project management of the Canadian Hydrogen Observatory and Radio-transient Detector

The Canadian Hydrogen Observatory and Radio-transient Detector (CHORD) is a new drift-scan radio interferometer operating from 300-1500 MHz, optimized for 21cm intensity mapping, 21cm galaxy detection, pulsars, and transient detection and localization. The full instrument will feature a core array of 512 six-meter dishes, plus two 64-dish outriggers at several thousand kilometer baselines. The project is nearing completion of the first 64-dish sub array, which will enable commissioning activities to begin in parallel with the remaining construction. In this presentation, we discuss the project management framework that has enabled us to navigate the logistical challenges of a fixed-budget, fixed-timeline research infrastructure project through a period of significant global economic and technological volatility.

astro-ph.IM

GHOST Commissioning Science Results: Identifying a new chemically peculiar star in Reticulum II

The Gemini High-resolution Optical SpecTrograph (GHOST) is the newest high resolution spectrograph to be developed for a large aperture telescope, recently deployed and commissioned at the Gemini-South telescope. In this paper, we present the first science results from the GHOST spectrograph taking during its commissioning runs. We have observed the bright metal-poor benchmark star HD 122563, along with two stars in the ultra faint dwarf galaxy, Ret II, one of which was previously identified as a candidate member, but did not have a previous detailed chemical abundance analysis. This star (GDR3 0928) is found to be a bona fide member of Ret II, and from a spectral synthesis analysis, it is also revealed to be a CEMP-r star, with significant enhancements in the several light elements (C, N, O, Na, Mg, and Si), in addition to featuring an r-process enhancement like many other Ret II stars. The light-element enhancements in this star resemble the abundance patterns seen in the CEMP-no stars of other ultra faint dwarf galaxies, and are thought to have been produced by an independent source from the r-process. These unusual abundance patterns are thought to be produced by faint supernovae, which may be produced by some of the earliest generations of stars.

astro-ph.GA